1. Field of the Disclosure
The present disclosure relates generally to orienting a tool and performing an operation in a wellbore.
2. Description of the Related Art
Many operations are performed in wellbores for recovery of hydrocarbons (oil and gas) include milling a portion of a casing in the wellbore or forming a lateral wellbore from a main cased or open wellbore. Windows are milled or the lateral wellbores are formed at specified locations in the main wellbore. To perform such a cutting operation, a downhole tool is conveyed in the wellbore that includes a whipstock connected to a cutting device or tool, such as a mill or drill bit. The cutting tool is typically operated by a fluid-driven motor, such as a progressive cavity motor. The downhole tool is rotated to orient the whipstock along the direction where the milling operation is desired to be performed. Once the tool is oriented, an anchor connected below the whipstock is positioned to fixedly set the whipstock along the desired direction. The mill is disengaged from the whipstock and moved along the drill whipstock to contact the wellbore. The mill is rotated to mill a window in the casing and/or to drill a lateral wellbore from the main wellbore. It is desirable to determine the whipstock orientation before setting the anchor and to determine the mill location relative to the whipstock depth (down the whipstock) when milling a window during a casing exit operation.
The disclosure herein provides apparatus and method for orienting the whipstock and determining location of the mill relative to the whipstock in a wellbore.